1. Field of the Invention
The present invention relates to an image processing apparatus and method for processing a predetermined original image in units of divided image data (by which is meant that the image data representing the image is divided into two or more portions, which are processed as units).
2. Description of the Related Art
Hitherto, when image data input using an image scanner is printed by an image output device such as a printer or a digital multifunction machine, the input image data is temporarily developed into raster type image data in an image memory of one page capacity. The raster type image data is then printed by the image output device.
Developing high-quality image data including data of four bytes per pixel in a raster manner in an A4 sized page (297 mm×210 mm) at a resolution of 600 dpi requires an enormous memory capacity, of about 140 M bytes. Requiring a large-capacity memory results in an increase in the cost of the device.
In recent years, techniques of dividing each page of image data into blocks, each having a predetermined size, and then performing image processing in units of divided image data, have been proposed in Japanese Patent Application Laid-Open No. 2002-008002 and the like. According to the technique using divided image data, image processing and storage processing capable of handling an entire page at once are not needed. The above-mentioned disadvantage of high cost can be sidestepped, resulting in an increase in image processing efficiency.
However, disadvantageously, when image data is handled as divided image data, in some cases, data management or image processing may be complicated. For example, when an image output device is interrupted due to a paper jam, the operation of recovering from the interrupt state may be complicated.